2 Answers
2

You should be able to use Google's Unlock Catpcha to unblock your application. I can't find much official doco on it, but according to this post if you unlock with the captcha logins for the next ten minutes are recognised as legitimate.

In fact, I do NOT have full authorization of the application, which, in my case, is sipsorcery. I just checked my sipsorcery account, and it turns out that my google account was set up as sip provider in sipsorcery. However, sipsorcery failed to register into google account, and I guess that google has prevented it to sign in. Any one has a solution for it?
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AlertJun 22 '12 at 4:49

Go into the the message and then, on the bottom right hand corner there should be a button that says details. Click that then choose 'Never show an alert for unusual activity' Then after 7 days it should stop sending you them alerts, in 7 days because they want to make sure that the 'bad guys' did not choose that. Then from then on you shouldn't be getting any more annoying alerts.